1. Field
One or more embodiments relate to an apparatus and method to concurrently display both two dimensional (2D) and three dimensional (3D) images, and more particularly, to an apparatus and method to concurrently display 2D and 3D images that may be applicable in TVs in homes, monitors, displays of portable devices, displays for advertisement and education, and the like.
2. Description of the Related Art
Techniques for displaying a three dimensional (3D) image may be briefly divided into glasses and a non-glasses types.
The glasses type may be further divided into an anaglyph type, a shutter-glasses type, a polarized-glasses type, and the like. The non-glasses type may mostly utilize a lenticular lens or a parallax barrier to implement the 3D image, and may be further divided into a stereo image displaying technique and a multi-view image displaying technique.
In displaying 3D images, various viewing inconveniences may occur that do not occur in 2D image displays. For example, the glasses-type stereo display may present the left and the right image sequentially or simultaneously depending on the display techniques, which results in users who do not wear the 3D glasses being discomforted by the overlapped images and feel dizzy.
Also, for the non-glasses case, there may exist an optimum 3D viewing position, which will be called herein the sweet spot, where the user can see the 3D images most clearly. As the sweet spot may be spatially limited and generally narrow, users who are located outside the sweet spot may see a distorted 3D image, which again may causes the users to suffer from dizziness and headaches.
In considering the home TV environment, some users may desire to watch 3D movie by wearing the 3D glasses, and at the same time other users may not want to wear such 3D glasses. Here, a problem exists in that users who do not wear 3D glasses can not watch even 2D images clearly, as well as also not being able to view the 3D image. Also in the non-glasses case, a few users may watch clear 3D image from the sweet spot, while other users may only view either 2D or 3D images with discomfort. Thus in both cases, some users who do not wear the 3D glasses or are not located on the precise sweet spot may experience severe discomfort, which makes such current 3D display techniques inadequate for the multi-user situation such as home TV or public display environment. Adding to this, some users, such as the elderly, may actually favor 2D images over 3D images. Thus, there is a need for a display apparatus which may enable a multi-user display technique to watch both 2D and 3D image at the same time without inconvenience.